<!DOCTYPE html>
<html>
  <head>
    <meta charset="utf-8">
    <title>offset-rotate interpolation</title>
    <link rel="author" title="Eric Willigers" href="mailto:ericwilligers@chromium.org">
    <link rel="help" href="https://drafts.fxtf.org/motion-1/#offset-rotate-property">
    <meta name="assert" content="offset-rotate supports animation.">
    <script src="/resources/testharness.js"></script>
    <script src="/resources/testharnessreport.js"></script>
    <script src="/css/support/interpolation-testcommon.js"></script>
  </head>
  <style>
    .parent {
      offset-rotate: 30deg;
    }
    .target {
      width: 80px;
      height: 80px;
      display: inline-block;
      background-color: black;
      margin-right: 5px;
      offset-rotate: 10deg;
    }
    .expected {
      background-color: green;
      margin-right: 15px;
    }
  </style>
  <body>
    <script>
      test_interpolation({
        property: 'offset-rotate',
        from: '100deg',
        to: '180deg',
      }, [
        {at: -1, expect: '20deg'},
        {at: 0, expect: '100deg'},
        {at: 0.125, expect: '110deg'},
        {at: 0.875, expect: '170deg'},
        {at: 1, expect: '180deg'},
        {at: 2, expect: '260deg'}
      ]);

      test_interpolation({
        property: 'offset-rotate',
        from: 'auto 45deg',
        to: 'auto 125deg',
      }, [
        {at: -1, expect: 'auto -35deg'},
        {at: 0, expect: 'auto 45deg'},
        {at: 0.125, expect: 'auto 55deg'},
        {at: 0.875, expect: 'auto 115deg'},
        {at: 1, expect: 'auto 125deg'},
        {at: 2, expect: 'auto 205deg'}
      ]);

      test_interpolation({
        property: 'offset-rotate',
        from: 'auto 170deg',
        to: '100grad auto',
      }, [
        {at: -1, expect: 'auto 250deg'},
        {at: 0, expect: 'auto 170deg'},
        {at: 0.125, expect: 'auto 160deg'},
        {at: 0.875, expect: 'auto 100deg'},
        {at: 1, expect: '100grad auto'},
        {at: 2, expect: 'auto 10deg'}
      ]);

      test_interpolation({
        property: 'offset-rotate',
        from: 'auto -280deg',
        to: 'auto calc(90deg - 0.5turn - 300grad + 0rad)',
      }, [
        {at: -1, expect: 'auto -200deg'},
        {at: 0, expect: 'auto -280deg'},
        {at: 0.125, expect: 'auto -290deg'},
        {at: 0.875, expect: 'auto -350deg'},
        {at: 1, expect: 'auto calc(90deg - 0.5turn - 300grad + 0rad)'},
        {at: 2, expect: 'auto -440deg'}
      ]);

      test_interpolation({
        property: 'offset-rotate',
        from: 'auto 100deg',
        to: 'reverse',
      }, [
        {at: -1, expect: 'auto 20deg'},
        {at: 0, expect: 'auto 100deg'},
        {at: 0.125, expect: 'auto 110deg'},
        {at: 0.875, expect: 'auto 170deg'},
        {at: 1, expect: 'reverse'},
        {at: 2, expect: 'auto 260deg'}
      ]);

      // No interpolation between auto/reverse and angle.
      test_no_interpolation({
        property: 'offset-rotate',
        from: 'reverse 90deg',
        to: '360deg',
      });

      test_no_interpolation({
        property: 'offset-rotate',
        from: '6rad',
        to: 'auto',
      });

      // Neutral keyframes use the inline style.
      test_interpolation({
        property: 'offset-rotate',
        from: neutralKeyframe,
        to: '20deg',
      }, [
        {at: -0.3, expect: '7deg'},
        {at: 0, expect: '10deg'},
        {at: 0.3, expect: '13deg'},
        {at: 0.6, expect: '16deg'},
        {at: 1, expect: '20deg'},
        {at: 1.5, expect: '25deg'},
      ]);

      // No interpolation to an angle from the initial value 'auto'.
      test_no_interpolation({
        property: 'offset-rotate',
        from: 'initial',
        to: '20deg',
      });

      // 'inherit' keyframes use the parent style.
      test_interpolation({
        property: 'offset-rotate',
        from: 'inherit',
        to: '20deg',
      }, [
        {at: -0.3, expect: '33deg'},
        {at: 0, expect: '30deg'},
        {at: 0.3, expect: '27deg'},
        {at: 0.6, expect: '24deg'},
        {at: 1, expect: '20deg'},
        {at: 1.5, expect: '15deg'},
      ]);

      // No interpolation to an angle from the initial value 'auto'.
      test_no_interpolation({
        property: 'offset-rotate',
        from: 'unset',
        to: '20deg',
      });

      // Interpolation between angles.
      test_interpolation({
        property: 'offset-rotate',
        from: '10deg',
        to: '50deg'
      }, [
        {at: -0.3, expect: '-2deg'},
        {at: 0, expect: '10deg'},
        {at: 0.3, expect: '22deg'},
        {at: 0.6, expect: '34deg'},
        {at: 1, expect: '50deg'},
        {at: 1.5, expect: '70deg'},
      ]);

      // Interpolation between auto angles.
      test_interpolation({
        property: 'offset-rotate',
        from: 'auto 10deg',
        to: 'auto 50deg'
      }, [
        {at: -0.3, expect: 'auto -2deg'},
        {at: 0, expect: 'auto 10deg'},
        {at: 0.3, expect: 'auto 22deg'},
        {at: 0.6, expect: 'auto 34deg'},
        {at: 1, expect: 'auto 50deg'},
        {at: 1.5, expect: 'auto 70deg'},
      ]);

      // 'reverse' is like 'auto 180deg'.
      test_interpolation({
        property: 'offset-rotate',
        from: 'reverse -170deg',
        to: 'reverse -130deg'
      }, [
        {at: -0.3, expect: 'auto -2deg'},
        {at: 0, expect: 'auto 10deg'},
        {at: 0.3, expect: 'auto 22deg'},
        {at: 0.6, expect: 'auto 34deg'},
        {at: 1, expect: 'auto 50deg'},
        {at: 1.5, expect: 'auto 70deg'},
      ]);

      // Interpolation between 'auto' and 'reverse'.
      test_interpolation({
        property: 'offset-rotate',
        from: 'auto 10deg',
        to: 'reverse -130deg'
      }, [
        {at: -0.3, expect: 'auto -2deg'},
        {at: 0, expect: 'auto 10deg'},
        {at: 0.3, expect: 'auto 22deg'},
        {at: 0.6, expect: 'auto 34deg'},
        {at: 1, expect: 'auto 50deg'},
        {at: 1.5, expect: 'auto 70deg'},
      ]);
      test_interpolation({
        property: 'offset-rotate',
        from: 'reverse -170deg',
        to: 'auto 50deg'
      }, [
        {at: -0.3, expect: 'auto -2deg'},
        {at: 0, expect: 'auto 10deg'},
        {at: 0.3, expect: 'auto 22deg'},
        {at: 0.6, expect: 'auto 34deg'},
        {at: 1, expect: 'auto 50deg'},
        {at: 1.5, expect: 'auto 70deg'},
      ]);

      // No interpolation between auto/reverse and angle.
      test_no_interpolation({
        property: 'offset-rotate',
        from: 'auto 200deg',
        to: '300deg'
      });
      test_no_interpolation({
        property: 'offset-rotate',
        from: '300deg',
        to: 'reverse 20deg'
      });
    </script>
  </body>
</html>
